Heretofore, a high frequency wave antenna for an automobile to receive digital TV broadcast band wave shown in FIG. 6 is reported in WO2006/001486. In this prior art example, a defogger constituted by a plurality of heater wires 43 and bus bars 45 is provided on a rear window glass plate 10, and an antenna conductor 41 and a feeding point 42 are provided. A uppermost heater wire right under the antenna conductor 41 has a meander shape. In this construction, in a digital TV broadcast band, influence of heater wires 43 and 44 to the antenna conductor 41 is reduced, and the antenna gain in the digital TV broadcast band is improved.
However, in this prior art example, since the heater wire 44 at the highest position is too long, its resistance per a unit length need to be reduced. Accordingly, the line width of the heater wire 34 at the highest position becomes too wide, and there has been a problem that the width of the heater wire 34 at the highest position prevents visibility.